conformal cooling mold for “venturi cup”
TRANSCRIPT
ConformalCoolingMoldfor“VenturiCup”PrecisionADMandMeletPlasticsInc.
MoldDesign:JeremySparling,P.Eng.DesignAnalysis:MatthewTessier,P.Eng.AdditiveManufacturing:JaredKozub,P.Eng.Report:AlanScarth
March 19th, 2017
Brief:
Awarpingdefectwasreportedintheproductionofa“VenturiCup”partmanufacturedbyMeletPlasticsInc.foruseinanAGCO-AmityJVairseeder.Thecustomerrequestedareductioninthewarpingseeninthelargerectangularsectionofthepart.Proposedalterationsincludedchangesinmaterial,wallthicknessandcoolanttemperature,aswellasanoptimizedmoldforcoolingproducedbyPrecisionADMusingadditivemanufacturingmethods.Theuseoftheoptimizedmoldtogetherwithadecreaseinwallthicknessresultedinawarpagereductionof42%;anoverallwarpagereductionof54%wasachievedwithallotheralterationsincluded.
ConformalCoolingOverview:
Oneofthelargestfactorscontributingtothedeformationofmoldedplasticpartsisthelackofuniformheatdistributionthroughoutthemold;differentareasoftheTinalpartcoolatdifferentratescreatinginternalstressesanddeformations.Usingconventionalmolddesign,coolantchannelsarerequiredtobedrilledasaseparateoperation,andarethusrestrictedtoapathofconnectingstraightlines.Thisrestrictionisthecauseofnon-uniformheatdistributionthatcausespartdeformation.Additivemanufacturingmethodscanbeusedtocreateamoldfeaturingacoolantchannelthatfollowsthecontoursofthemold.Thisdrasticallyimprovestheheatdistributionduringcooling,andeliminatestheneedtodrillthecoolingchannels.
March 19th, 2017
Figure1:OriginalParts Figure2:ImprovedParts
ImpactofRespectiveInputs: TheinputsidentiTiedasfactorsthatreducedwarpingareasfollows:-MaterialChange:
ThematerialusedwaschangedfromRhetechGC15P200-01UVtoRhetechS26282.01.ItwasidentiTiedbythesupplierashavingsimilarphysicalpropertiesbutlesspronetowarping.Thismaterialchangealoneresultedina3%warpagereduction,butwhenpairedwiththeconformalcoolingmoldandcoolantalterationthereductionwas7%.
-ConformalCoolingandWallthickness: The3DprintedmoldinsertmanufacturedbyPrecisionADMandareductioninwallthicknessfortheTinalpart(from.110”to.080”).Theseinputsbothalteredthemoldgeometryandasaresulttheimpactofeachcouldnotbeevaluatedindividually.Togethertheycreateda42%reductioninwarpageusingtheoriginalmaterialanda44%reductionusingthenewmaterial.
-CoolantTemperature: Differentcoolanttemperatureswereusedindifferentpartsofthemoldratherthanoneuniformtemperaturethroughout.ThisselectiveapplicationofcoolantcouldonlybeconductedusingtheConformalCoolinginsert,andreducedthewarpage9%furtherusingthepreviousmaterial.Thisincreasedto15%usingthenewmaterial.
March 19th, 2017
Figure3:Previouslyusedmoldwithstraightcoolantchannels
Figure4:Printedmoldinsertwithconformalcoolantchannel
Results:
Thecumulativeeffectofallalterationsmadeintheproductionof“VenturiCup”partswasa54%reductioninwarpagefromtheoriginalparts.Whenviewedasanindependentvariable(withtheexceptionofwallthicknessalterations),theconformalcoolinginsertprintedbyPrecisionADMproduceda42%reductioninwarpage.Thisapplicationofadditivemanufacturingshowcasesthecomplexsubsurfacegeometriesthatarepossibleusingthemethod.WhileincreasingthequalityoftheTinalproduct,thisoneoffpartalsoeliminatestheneedtodrillcoolantchannelsafterthemoldhasbeenformed.ResultsandCADmodelsobtainedfromthisprojectweresuppliedbyMeletPlasticInc.
March 19th, 2017